Theoretical Analysis of the Catalytic Cycle of a Nickel Cross-Coupling Process: Application of the Energetic Span Model

The nickel-catalyzed cross-coupling of an anhydride with an organozinc: reagent was studied theoretically. The energetic span model (Kozuch, S.; Shaik, S. J. Am. Chem. Soc. 2006, 128, 3355; Kozuch, S.; Shaik, S. J. Phys. Chem. A 2008, 112, 6032) was employed in order to analyze the observed kinetic behavior (Johnson, J. B.; Bercot, E. A.; Rowley, J. M.; Coates, G. W.; Rovis, T. J. Am. Chem. Soc. 2007, 1298, 2718). The computed energy profile, combined with the energetic span model, enables modeling faithfully intriguing experimental findings such as the independence of the rate on anhydride concentration, first-order kinetics with low organozinc concentration, and zero-order kinetics at high concentration. Two species were identified as being responsible for the overall kinetics of the catalytic cycle: the transition state for the product release and the oxidized Ni-II complex.